Hydraulic variable slip coupling



Oct. 30, 1951 G. w. BALL 2,572,834r

HYDRAULIC VARIABLE SLIP COUPLING Filed Jurle 1l, 1946 U 3 Sheets-Shee l A\\\\\\\ \\l` \w E co o al) N 53@ w- Ss N o E 9- L m 4k o A N A c :n

1 l f g y N o g g @www GEORGE W. BALL FLQIQ QB ou. SUPPLY Oct. 30, 1951 G. w. BALL 2,572,834

HYDRAULIC VARIABLE SLIP COUPLING Filed June ll, 1946 3 Sheets-Sheet 2 l l42 k 2' b I4 8- u l5 f le *A wa/wtm l2 GEORGE w. BALL Pfg; 3 m l www Oct. 30, 1951 F'iled June ll, 1946 Supercharger Drfve H Coupling R.P.M. In Thousands I-P Slip Loss to Huid G. w. BALL.

HYDRAULIC VARIABLE SLIP couPLING 5 Sheets-Sheet 3 O l 2 4 5 6 7 B Superchurger- Speed In Thousands R.P.M.

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O l 2 Supercharger Speed In Thousands R.P.M.

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GEORGE W. BALL S11/UWM Patented Oct. 30, 1951 HYDRAULIC VARIABLE SLIP COUPLING George W. Ball, Hartford, Conn.

Application June 11, 1946, Serial No. 676,044

9 claims. (C1. 'r4- 688) (Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) This invention relates to a novel form of variable slip multi-stage hydraulic coupling.

The conventional Fottinger kinetic hydraulic coupling comprises two rotatable elements, a driver element and a driven element. For mul-tistage operation in driving superchargers, fans or blowers, two or more of such units lmust be arranged so that each unit drives through a separate gear train to a common shaft. To prevent power feed-back, such arrangements mus-t be provided with special quick acting valves with means for accurately timing their actuation in order to prevent fluid entering any unit except the one carrying the load. These requirements must necessarily be the basis of all designs or arrangements utilizing the Fottinger uid coupling for multi-stage operation. Circulation of air in evacuated coupling units results in unpreventable feed-back losses. Such objectional characteristics as speed surges and momentary loss in drive are difficult to prevent when mechanical shifter valves are used, and are particularly objectionable' in aircraft power plants. In the conventional arrangements, the coupling units are driven at different speeds and usually drive a common shaft by different diameter gears. excessive space.

In this application two coupling units are constructed in tandem making a two stage unit. This coupling unit is unique in that the first stage driver is integral with the second stage runner and therefore is driven hydraulically when the second stage is in operation. Due to this intimate arrangement, the second stage chambercan receive fluid directly from the rst stage through appropriately located overow passages and the entire unit can be supplied through a single valveless fluid passage. The coupling components are in fact hydraulically in series. Advantages over conventional arrangements include: compactness, decreased weight, simplicity of control, elimination of feed-back losses and increased reliability due to the elimination of mechanical valves. The coupling output or load is varied by merely regulating the mass flow of fluid in the single supply passage by means of any conventional hydromechanical regulator device. Such devices are available which are sensitive to changes in density, pressure, lspeed gr tempera- Such arrangements inherently require ture. In this application, two-stage operation is obtained by only three rotating elements since the first-stage driver and the second-stage runner arecombined into one integral rotating element. Completely variable slip in both stages is obtained by varying the fullness of the unit as determined by the fluid flow balance between the coupling vents and the supply. l

An object of this invention is to combinesuch two-stage variable slip hydraulic couplingwith planetary or spur gear drives for driving variable.

speed devices such as engine superchargers, air-` plane cabin superchargers, fans or constant speed devices if controlled by a Ahydromechanical speed governor.

More speoiflcally an object is to combine such two-stage variable slip hydraulic couplingwith a planetary system wherein the runner of theV first stage is provided with an integral rotatable'y ring gear for driving planetary pinions mounted on a rotatable planetary spider and in turn meshing with a sun gear mounted on the driven member. The driver of the second stage is provided to the second-stage runner which is integral with the first-stage driver. The loading of the second stage is controlled by the volume' overow of fluid received from the rst stage.

Another object is to combine such two-stage variable slip hydraulic coupling with a planetary gear system wherein the runner of the rst stage is provided with a sun gear for driving planetaryvv pinions mounted on a rotatable planetary spider and meshing with a stationary ring gear, the spider being keyed to or integral with the driven member, and wherein the second stage driver is driven at a higher speed than the rst stagev driver, the rst stage driver being driven through an overrunning clutch so that its speed may be increased by the second stage ,driver when the second stage is placed into operation by increased fullness of the second stage due to a controlled overflow of iluid from the first stage.

Another object is to provide the rotatable ring gear runner of a planetary gear such as defined in the penultimate paragraph above, with a roller one-way lock to prevent its free rotation with respect to the driver thereby providing direct drive from the main drive shaft through the planetary system to the driven member accomplishing a minimum operating speed ratio when the fluid supply through the coupling is shut off.

Another object is to provide the first stage driver of couplings such as defined above with a normally released clutch member for cooperation with a shoe integral with the first stage runner and means for locking these members together in response to operation of the second stage.

Another object is to provide the two-stage variable slip hydraulic planetary drive defined above with both features specied in the two preceding paragraphs. Y Y

The use of variable slip two-stage couplings as defined above is not necessarily limited to cooperation with planetary gear systems as .will become apparent in the following detailed description of illustrative devices based on the present invention, having reference to the accompanying drawings, wherein:

Fig. 1 is a sectional view of the two-stage variable slip hydraulic Acoupling combined with a' planetary gear system to drive a supercharger;

Fig. 2 is a similar sectional View of the twostage variable slip hydraulic coupling combined with va planetary reduction gear system for driving a fan; v

Fig. 3 is a partial detailed sectional view of a two-stage variable slip hydraulic coupling similar to that in Fig. 1, provided with a roller one-way clutch lock for the rotatable ring gear, and an automatically controlled clutch means between the first stage driver and runner;

Figs. 4, 5 and 6 are calculated characteristic curves illustrating the operation of this type of coupling as applied to a supercharger which is assumed to require 400 horsepower at 20,000 R.' P. M., the planetary system having a gear ratio of 2.7 to 1;

lg. 7 is a sectional view of the roller one-way clutchitaken on line 'I-T of Fig. l.; and

Fig. 8 is a partial detailed sectional View of al .two-stage hydraulic coupling similar to Fig. 2, provided with an automatic controllable clutch.

As normally used for driving superchargers, the Fottinger kinetic coupling .is utilized as a hydraulic clutch operating at minimum slip `and cooperating between driving and driven members.

Only a single speed ratio is possible if the full-- ness of the coupling is not varied. Staging may be accomplished by adding 'additional coupling. However, each must drive the common driven member through a separate gear train and contain provision for shutting off the uid supply when not carrying the load. Such arrangements are exemplified in Patents 2,415,760 to Porter, Italian patent to Daimler-Benz No. 366,358, and Patent 2,385,834 to Nallinger.

If variable slip operation is desired, it also is necessary to provides means for varying the fullness of each unit when in operation. The complicated valve mechanisms required to accomplish .multi-stage operation with the above arnangements and related difficulties generally preclude their use for driving such Adevices as engine superchargers, cooling fans or cabin superchargers.

The-device in the present disclosureis essensarily limited to two stages and may be used in conjunction with any configuration of gearing forming a gear drive. The devices illustrated in the figures of the drawings include a .two-stage variable slip coupling in :combination `with a planetary gear drive in Fig. 1 for driving a, supercharger, and a similar coupling in combination with a planetary gear drive in Fig. 2 for driving a fan. The vadditional features of a roller oneway lock for the rotatable ring gear, and automatic clutch means between the first stage runner and the first stage driver are illustrated in Fig. 3. The one way lock and automatic clutch means are refinements not essential for the operation or utility of the coupling.

Referring to Fig. l, the first stage driver Il is driven through a one-Way roller clutch I0 by drive gear A6 from double drive gears 5. Second stage driver 8 is driven at a relatively higher speed by drive gear 5 through gear 1,. Drive gears 5 are operated by intermediate pinions 2 driven by the main coupling drive gear I which is mounted on main drive shaft I9. The pinion shafts are mounted in bearings in the couplingl drive support housing 3 .and coupling drive pinion support housing 4. Thus the first stage driver II and second stage driverv 8 .are rotated in ,a direction counter to the main drive shaft I9 and at relatively different speeds. The first stage runner 23 is attached to .or .integral with a ring gear I5 which meshes with planetary pinions I6 mounted on a spider I2 keyed to drive shaft I9.

" Pinions I6 mesh with the sun gear I1 which is connected to drive the supercharger I8. The. operating f iuid `is supplied to passage 2.4 the. an-v nular groove 25, passages 26 .21 and 28 in the drive shaft I9, annular groove 29, passages 30 in the drive gear 6, annular groove 3| `and passages 3.2 in the first stage driver to the first lstage uid chamber I3 for operation of the first :stage unit Il, 23,. kCalibrated bleedsV 20 and 20' provide vfor continual withdrawal of the operating fluid from each stage, the slip being varied by varying the supply of fluid. By further increasing the supply of operating fluid to the rst stage .fluid chamber I3 after the first stage runner 23 has attained its minimum slip with respect to the first stage driver II, the operating iiuid may be caused to overow from the first stage fluid chamber into the second stage fluid cham-ber 9 through overflow passages 2l. When chamber 9 is sufficiently full, the second stage driver 8 will impart a driving torque, due to its higher speed -of rotation to the first stage driver I I, thus increasing its speed as permitted by the overrunning clutch I0. This increase in speed will be imparted to the first stage runner 23 since its slip with respect to driver II is at a minimum, and, as a result, the speed of the supercharger I8 also is tproportionately increased. Maximum speed is obtained when the supply of fluid is maintained suiciently to cause operation at minimum slip between-driver 8 and driver I I.

Sealing members 33 ,and .34 `are Ishown between the Adriver II and driver ,8 and runner 23, and sealing means 35 land 36 are. provided-,onzthe sides of fluid :chambers 9 and 4.3 respectively. {Ilhese sealing means, however, may be omitted becausev the centrifugal force acting on the fluid in the fluid chambers will maintain it in the outer periphery of these chambers and Will normally prevent its escape through these openings. A planetary ring gear support bearing I4 is provided between the spider I2 and the planetary ring gear I5.

In Fig. 2, a similar variable slip hydraulic coupling is shown combined with a planetary gear drive wherein the first stage driver I I is provided with a 'drive gear 6 and the second stage driver 8 is provided with a gear I driven by double pinions 5' as in Fig. l by the intermediate pinions 2 which are driven by gear 31 mounted on the main drive shaft I9. The first stage runner 23 in'this case is provided with a sun gear 38 (instead of the ring gear I5 of Fig. 1) for driving the planetary pinions I6 mounted on a spider I2 which in this case, is attached to or integral with the fan shaft 39 for driving the fan 40. The planetary pinions I6, in this case, mesh with a stationary ring gear 4 I.

In the rst of the above devices as shown in Fig. 1, the ring gear I5 may be further provided with a roller one-way brake lock 42, and also with one member 43 of a ring clutch, the other ring member 44 of this clutch being operated into clutching position by plungers 45 operating in fluid chambers 46 spaced at equal intervals around the periphery of the rst stage driver. The plungers 45 being normally retracted into clutch release position by springs 4'I. These fluid chambers are connected by relatively large openings 48 tothe second stage fluid chamber 9 and the bleeds 20' for fluid chamber 9 are in this case omitted and are substituted by bleeds' 49 in the plunger fluid chambers 46. Vents 50 arel provided in the plunger cylinders for relief purposes.

In a planetary system in which the ring gear is locked and the spider driven, the R. P. M. of the sun gear is N=S+SR where S is the R. P. M. of the spider and R is the ratio of the teeth cn the ring gear to the teeth on the sun gear. However, if the ring gear is mounted on a bearing and driven in a direction counter to that of the spider, a further increase in the R. P. M. of thesun gear will be obtained, this increase being proportional to VR where V is the R. P. M. of the ring gear. 'I he R. P. M. of the sun gear then becomes N=S|SRIVR- If the ring gear is not driven, there is n0 relative motion of the components of the planetary, and V=S and N :S

In the following description of the operation of the device of Fig. 1, V denotes the R. P. M. of the runner 23 when in rst'stage operation and V denotes the R. P. M. of runner 23 when in second stage operation.

Such a planetary system is particularly adapted for driving high speed devices such as superchargers when combined with a variable slip coupling. The coupling proposed in this application is particularly adapted for cooperation with such planetary system as shown in Fig. 1. Referring to Fig. l, with the coupling void of fluid, the planetary system including 23, I5, I2, I6,. I'I and the supercharger I8 rotate with the main drive shaft I9. Except as caused by friction and the resistance of the supercharger I8, there would be no relative motion between gears I5, I6 and I'I.

When the operating fluid is introduced through passage 32 into the rst stage fluid chamber I3, driver II imparts kinetic energy to the fluid and directs it against the runner 23, so that the speed of runner 23 is gradually reduced because the runner 23 no longer rotates freely in response to the drive from member I2 keyed to drive shaft I9.

The retarding of the free rotation of the runner 23, which is integral with ring gear I5, results in relative motion between the planetary gear components I5, I6 and I'I, causing an increase in speed of the supercharger I8 in the same direction as the main drive shaft I9. Upon further increase in the supply of fluid, the runner 23 is retarded until rotation ceases. At this condition the supercharger I8 R. P. M. is N=S|SR, as defined above. Upon further increase in the supply of fluid, the slip between driver Il and runner 23 is further reduced resulting in runner 23 being r0- tated in the same direction as driver II, thereby further increasing the R. P. M. of the supercharger. Upon increasing the fullness until minimum slip is obtained, the supercharger I8 will have attained a speed of N=S+SR|VR Where V is the R. P. M. of runner 23 or ring gear I5. Upon further increasing the supply of fluid to overcome the escape through bleed 20, overflow through passages 2| into chamber 9 will be accomplished. When this chamber is sufficiently filled, the second stage driver 8 imparts kinetic energy to the fluid and directs it against the runner vanes 22, which are integral with the driver II thereby imparting a driving torque sufficientA to cause driver I I to rotate at a speed higher than permissible by drive gear 6. This increased speed of driver I I is permitted by the overrunning clutch III. Since the slip between driver II and runner 23 is at a minimum, this increased speed will be transmitted to runner 23 resulting in increased relative motion between lthe planetary components I5, I6 and I'I, and a further increase in the speed of the supercharger I8. Upon increasing the fullness of chamber 9, minimum slip between driver 8 and driver II Will be obtained. The maximum R. P. M. of the supercharger I8 is N=SISR|VR where V is the R. P. M. of the runner 23 and ring gear I5. It will be seen that V is equal to the R. P. M. of driver 8 minus the sum of the slips between drivers 8 and Il, and driver II and runner 23. A reduction in supercharger speed is effected'by the reduction in the supply of fluid. Since the escape of fluid from chamber 9 is provided by bleed 20', and the supply of fluid to chamber 9 is by overflow from chamber I3 through passages 2I, it is clear that any reduction in total fluid supply Will result in a decrease in the fullness of chamber 9 and an increase in slip between d river 8 and driver I I, and consequently a decrease in the value of V and speed of supercharger I8. Upon further reduction in the supply of fluid, chamber 9 will subsequently become void and driver I I will again be driven through gear 6 and roller clutch I 0. Upon further reduction in fluid the slip between the .driver I I and runner 23 further increases until rotation of runner 23 and ring gear I5 ceases. At this condition V'=O and the speed of supercharger I8 is NzS-i-SR. Upon further reduction in the supply of fluid, the slip increases further causing runner 23 to begin rotating in the same direction as drive shaft I9. The value of V then becomes negative and, when the chamber I3 is void of fluid, equal t0 the value .of S when variable speed is permissible and controllable in' Since at this point V 1 thev supercharger speed .range -zbetween 'N -S :and themaximum .design speed.

The .operation of the :device as shown Fig. 2 is fsimilar to that of .the device'of Fig. 1, and has the 4same advantageous characteristic 'of smooth transition Abetween Astagos without the use -fof `mechanical valves. However, in this application, thefdirection of rotation of the drivers 8 and .I-I isimmaterial, since the co'uplingrunner-ZS merely rotates the sun gear 38 of a planetary Areduction drive 'consisting of :fixed ring gear 4I and planetary :pinions I6 mounted on spider zI2 which in turn'is connected toifanzshaft 39.

- VIn order to positively eliminate theslip `between driver II 'and runner 23 a clutch device such .as shown at 43--44 in Fig. 3 may be incorporated. This Vdevice may include a minimum of three plunger cylinders or fiucl chambers 46 containing fluid operated spring-returned plungers45 located at the periphery of driver I I. The axes `of these cylinders 'or chambers are parallel with vthe axis of .rotation of the coupling and are'equally spaced around the periphery. The ends 'of the plungers 45 operate against 4a clutch ring 44 which is pressed against a facing 43 attached to fa ring 43 which in turn lis attached to 4or integral Awith the rngfgear I5 or driven member 23 of the `fi-rst stage. In thisrapplication the second stage bleeds 20 are replaced by bleeds 49 in the `plunger cylinder. The operating uid is supplied through relatively large supply :passages 48 tothe plunger 'cylinders from .uid chamber 9. The iirst stage bleeds 20 are so located, in this case, that the plungergu-.ides 5I override these Vbleeds lthereby shutting `off the fluid 'escape when the Apluri-gers are actuated. Since the transition from the first stage operation te Second stage `operation is accomplished by increasing the iiuidflow tothe chamber I3 -until the fluid overflows through passages 2I into chamber 9, the plunger chambers 46 will be iilled, causing the plunger guides 5I -to override the first stage bleeds 29. The total fluid iiow then passes into the second stage fluid chamber 4 9 thereby -accelerating the vfilling of the plunger zchambers46- Due to the speed of rotation, .suiiicient dynamic iiuid pressure will be available to cause the plungers 45 -to move against the force of springs 41 and .press clutch ring 44 against facing 43 thereby .locking or clutching together driver II and runner 23. This engagement will take place without shock since the minimum vslip for couplings of this type is only approximately 2.5% to 3%. the clutch device will accelerate the transition from the rst or low to the second or high stage, and will eliminate the 2.5% to 3% slip loss in the rst stage during the time the second stage is in operation. Since the slip in the first stage is eliminated, there will be n heat added to the duid in passing from the first into the second stage chamber 9. The total fluid iiow after operation in the second stage has been initiated, "will not have to be much more than that necessary for operating in the second stage since the lfirst stage bleeds 20 kwill 'be sealed on. Operation in the second stage Will, of course, result in higher speed lof rotation of driver II and consequently higher dynamic fluid pressure in chambers r46 will befavailable.

In the use of these couplings for main stage superchargers, using spinner fuel injection Aor for other reasons, it may be desirable to constrain the ring gear I5 of the planetary drive Isystem (Fig. 1) from rotating with driveshaft -I'9 in order to satisfy :a minimum .speed requirement. A

While not essential to operation, the use of 8 means -of"accoinplishing Athis is vthe ,provision vvof -a free-Wheeling brake, or roller one-way brake lock, as shown at 42 in Fig. 3. This will preventfthe initial rotation of the ring Ygear vI5 and first stage runner 23 in the direction of operation of the accessory driveshaft I9, and Will result ina minimum speed of the supercharger I8 in accordance with the expression N :S -1-SR (as previously dened) in response to operation of the drivevshaft I9. This :minimum speed of the supercharger I8 will be maintained until the coupling Vtakes -eiect to'drive therunner 23 and ring gear I5 counter I-to the direction of drive shaft I9 thereby increasing the supercharger I8 speed further, as previously described. J

'The 'advantages in the use of the above -hdraulic coupling means may be enumerated asVv follows:

1. The'drive can vbe compactly'designed, thereby saving weight and space.

2. The coupling unit can be enclosed by a 'fluid collector Aallowing the use of a fluid system vinclependent of the engine oil system, and the possible use of vlow Viscosity non-sludging fluid.

3. Automatic control is simplified by the use of the-single -fluid supply passage since it is notnecessary to time and control the iiuid Vflow to each stage independently.

4. Since the unit can becentrally located Within the engine, couplings of Vrelatively large diameter can "be used. This permits the use 'of 'relatively low coupling rotational speeds, resulting in lower stresses Aand windage losses. It will be noted that the power transmitting capacity of a kinetic fluid coupling is proportional to the cube of thed-rivfirrg speed and the 5th power of the diameter' (HP=N3D5C, where C isa design constant, N is the R. P. M. of the runner, and D is the effective diameter lof the lperipheral iiuid chamber).

i5. The ldesign allows considerable latitude 1in the choice of speed ratios yof the various components andthe percentage of power to vbe carried by leach stage depending upon design requirements.

6. Since mechanical `valves required by successive operation ofthe stages are eliminated, the transition between stages will be smoother and more reliable than obtained With conventional couplings.

7. The power or driving torque resulting `from air circulation through the coupling units when empty of fluid does not result in drag `of any component of the coupling drive. Air circulates in kinetic couplings in the same manner as fluid, thereby resulting in a torque being transmitted from the driver to the runner. While this load is small, as it is proportional to the density of air as compared to fluid, it may result in losses of considera-ble magnitude in large couplings.

8. In -conventional arrangements for multistage operation, although vthe fluid is shut oft-from couplings not -carrying the load, the runners A.of such units being attached to the common driven element actually rotate at some higher speed thanv the drivers resulting in a feed-back loss. design proposed in this application, such feedback Vloss does not occur since air load in either stage drives the driven member. In conventional arrangements, feed back power must be supplied,

by the higher stage coupling in addition to the normal requirement usually resulting in over stressing the high stage components.

The curves, Figs. 4 t0 6, are all based on the.

sameabscissae of supercharger speeds from 0 to 29,090.13. P.. M., Fig. Y4 using the horsepower gloss` In the:

due to slip for the ordinates, Fig. 5, the required speed of the coupling runner in this application (Fig. 1) as compared to conventional arrangements; and Fig. 6, the horsepower assumed to be required to drive the supercharger.

Curve A in Fig. 4 shows the horsepower loss which would occur if only one stage of a particular hydraulic coupling, such as the first stage illustrated, were used throughout the entire range of speeds. Curve B indicates the loss for a single stage coupling, such as the first stage illustrated, when used for a lower range of speeds, whereas curve C results from the use of two stages in combination asv in the illustrated device, showing the overall reduction in slip losses over those obtained with a single stage for the entire range f speeds as indicated by the curve A. Curve C represents a further reduction in losses when three stages are utilized. The double line at B represents two curves, one for the coupling such as used for the rst stage of the illustrated device and one for a similar coupling used in a conventional spur gear drive, indicating the difference in gear arrangement makes a negligible difference in the slip losses of the coupling.

In Fig. 5 curve D represents the required speed of the planetary ring gear or runner as used in the device of Fig. 1, whereas curve E was calculated to represent the required relative speed of the runner of a coupling used in a conventional spur gear arrangement. This curve indicates that conventionally arranged couplings must be driven at a higher speed to obtain the same resultant supercharger speed than inthe case of the device illustrated in Fig. l.

The above curves A, B, C, D and E were calculated from the assumption that the power required t0 drive the supercharger was as illustrated by curve F of Fig. 6, and the gear ratios were assumed to be 2.7:1 in the illustrated device of Fig. 1.

Curve C in Fig. 4 shows the slip loss characteristics of a three-stage coupling unit, if an intermediate stage were introduced between the twostages of the device illustrated in Fig. 1. A further reduction in slip losses could thus be obtained if deemed desirable as indicated by this curve.

Obviously, the dimensions of parts, gear ratios and arrangement of gears may be varied to suit different requirements and applications, the proportioning of components of the devices Vhere shown being exaggerated for purposesof illustration. Although Figs. 1 and 2 show the application of the coupling to planetary gear systems, the use is not limited thereto.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

What is claimed is:

1. A multi-stage hydraulic variable slip coupling having a driving means and a driven member, comprising a first stage driver geared to the driving means through an overrunning clutch, a 'u creased by *thel succeeding stage driver over `the normal direct drive from `the driving means through their respective overrunning clutches, and bleed means for each stage.

2. A multi-stage hydraulic variable slip cou-.- pling having a driving means and a driven member, comprising a irststage driver geared vto the driving means through an overrunning clutch, a first stage runner hydraulically driven by said .first stage driver and geared to said drivenmem- 4ber, atleast one additional driver geared to the driving means to operate at successively relatively greater Vspeeds than, and in the same direction as, said rst stage driver for hydraulically driving said first stage driver and eachsuccessive stage driver, all drivers except that in the last stage being provided with overrunning clutches and runner vanes to .permit their speeds being vincreased by the succeeding stage driver over-the normal direct drive from the driving means throughA their respective overrunning clutches, and common fluid supplyV passage means for the hydraulic fluid chambers to bring them successively into operation by overflow from the firststage fluid chamber to the second stage fluid chamberand then to each succeeding chamber as the previous stage reduces. its slip to a minimum, and bleed means for each stage.

3. In a hydraulic coupling, a drive shaft, a driven shaft, a driver forming a peripheral fluid chamber about said drive shaft and geared thereto to turn at any desirable gear ratio, a runner in said fluid chamber having a sun gear, planetary pinions, meshing with said sun gear, a spider for said pinions mounted on said driven shaft, and a fixed ring-gear meshing with said pinions, means for admitting iiuid to said fluid chamber, and bleed means for said chamber. f

4. In a hydraulic coupling, a drive shaft, va driven shaft, a driver forming a peripheral fluid chamber rotatably mounted around said-drive shaft, gear means including overrunning clutch means operatively connecting said driver to said drive shaft to be driven in the opposite direction therefrom, a runner in said fiuid vchamber having a rotatable ring-gear integral therewith, planetary pinions meshing with said ring gear, a spider for mounting said planetary pinions and rigidly mounted on said drive shaft, a sun gear on said driven shaft meshing with said planetary pinions, means for admitting a supply of operating fluid to said iiuid chamber, said driver and runner constituting a first stage, a second stage, said second stage comprising a second runner formed on the first stage driver and forming therewith a second peripheral fluid chamber, overflow passages between said fluid chambers for delivering operating fluid to said second fluid chamber after said rst fluid chamber is substantially filled, a second driver cooperating with said second runner, gearing between saidv drive shaft and said second driver to operate said second driver at a higher reverse speed than said rst driver, said overrunning clutch means providing an Yarrangement whereby said first driver may be hydraulically driven by said second driver atv a higher speed than the first driver is driven directly by said drive shaft, and bleed means for the fluid in each chamber.

. 5. In a hydraulic coupling, a drive shaftffa driven shaft, a driver forming a peripheral fluid chamber rotatably mounted around said drive shaft, gear. means including overrunning clutch means operatively connectingv said driver Vvto said drive shaft to vbe driven in the opposite direction :all therefroni, V`arunrwrcin saidfnuid chamberihaving ea lrotatable ring-.gear :integral therewith, plane- .taey-pinions meshing .Withzsaidring igear, :a a Spider for mounting said planetary pinions and .rigidly vmounted onsaidfdriveshaft,ciaasungear on said driven shaft :meshing .with .said planetary apindons, ,means for admitting asupply .of operating .luid to said fluid chamber, said l.driver ,and runmer. constituting a .first stage, asecondistagegsaid -second stage comprising va .second runner formed :on the .'-rst stage idriver land v:forming `:therewith a :second peripheral Jfluid chamber, :overow passages between said. uid chambers for idelivering A.operating ,.fluid :to said second fluid ychamber raiter saidxrst chamber is filled, a second A.driver :cooperating With said second runner, .gearing lbetween said drivezshaftlgandrsaid second driver to foperate .said second driver at :a higher reverse speed =than said first driver, `said :overrunning .clutch meansprovidingan arrangement whereby ,20

said .grst driver maybe hydraulically driven :by saidseconddriver-.ata higher-.speed than the rst driver ;is driven .directly'by said drive shaft, .-bleed means for ythe :uid in feach chamber, v.friction clutchmeans `between said first stage runner and .said nrst driver normally released, ;and imeans responsive to -fluid .flow 4into said second `@chamber for operating said clutch :means into .engaged position for Flocking said rst stage driver .and runner members :together whenrsaidsecond stage yisfbrought vinto operation.

. 6. .In :a hydraulic "coupling, .a .drive shaft, .a driven'shafua driver forming `a peripheral uid chamber rotatably mounted around :said drive shaft, `gear :means 'including overrunning .clutch means -operatively .connecting said driver to said drive shaft to be driven inthe opposite direction therefrom, a runner Yins'aid uid chamber Vhaving a Y-rotatalce ringegear integral therewith, .planetary pinions meshing Withisaidirring-gear, a spider 'for mounting said planetary pinions .and rigidly mounted-on 'said ,drive-:sham afsunfgear on. said driven shaft vmeshing lwith said planetary pinions, `means for :admitting a supply of operating iluid to `said iiuid chamber, .said driver .and runner constituting Ya iirst stage, asecond stage, said .second stage comprising .a second frunner formed on the frst stage driver and .forming therewith .a second .peripheral uid chamber, over'iow 'passages between said ffluid chambers for .deliveringbperating lfluid :to said second Afluid chamber vafter said :first .chamber v.is f1lled,:,a..sec ond :driver cooperating with said `second runner, gearing .between ,said drive vshaft and isaid :second driver to operate said second .driver .at a higher reverse speed :than said firstdriver, .said overrunningclutchmeans .providing an arrangement whereby #said '.rst driver may be fhydrau, lically drivenby saidsecond driver ;at.a..higher speed than the .first driver is driven directly by saiddrive shaft, bleed means for Lthe luidsineach chamber, and one-way constraining :means on said ring gear for preventing its initial turning inthe-direction of the drive shaft and .providing for a minimum relative speed ojf operation ofsaid driven shaft with respectgto said .drive shaft.

7,. .In a .-hydraulic coupling, a drive fshatt, 1a driven shaft, a ,driver forming a peripheral uid chamber rotatably mounted around said drive shaft, gear :means including -overrunning .clutch meansloperatively .connecting said driver to: said drive shaft to be driven ginfthe opposite direction therefrom, va runner inisaid =uid `chamber having a .rotatable ring-.gear vintegral therewith, planetary zpinions meshing with said 4ring-gear, a

L32 spider :for :mounting .said lplanetary pin'ions and rigidly amounted :on fsaid drive tshaft, i'a sun .gear -onsaid fdrivenshaftf'meshing"withfsaid planetary pinions, fmeansyior admitting a supply fof operat.i

ing fluid to said -uidfchambergsaid driverfand :runner constituting a arst stage, asecondtstage, vsaid :second stage -comprising .a second vrunner .formed :on :the gfirst stage :driver and 1forming therewith ta second -peripheral .fluid chamber, .overow ,passages between Ysaid fluid chambers lfor delivering :operating huid rter-said second Afluid :chamber after -saidnrst-chamber -is filled, assec ond Vdriver cooperating with :said vsecond irunner, gearing between -said 'drive vlshaft and said Vsecond .driverlto operatersaid second driver at -ahgher reverse speedthan said ;rst driver, vsaidroverrunning :clutch means kproviding =an arrangement whereby said first driver may -b'e hydraulically driven .by said second driver vat -a higher speed than the rst driver .is driven directly :bysaid drive shaft, vbleed tmeans for the fluid in :each chamber, friction clutch-.means'between said rst stage runner andfsaid rststage driver normally released, Vmeans responsive to :fluid flow intosaid second chamber for loperating said .clutchimeans into yengaged positioni'for .locking saidrst stage driver and runner :members together whengsaid second-stage is broughtfinto operation, and :.onefway constraining `means on said .ring gear for preventing its initial turning dn v.the directioncf the drive lshaft and providing for .a :minimum relative speed of -operation of said driven shaft withrespect to said dri-ve shaft.

8. In a hydraulic coupling, Ya .dri-ve. shaft, za driven shaft, a driver =formingragperipheral fluid chamber-aboutsaid idrive shaft, fgear means including -an Yoverrunning clutch operatively .conf necting said driver to .said shaft `.to turn ,said driver at any .predetermined .desirable I, gear zratio, a runner in said/fluid chamber having-a-snn gear operatively connected thereto, planetary .pinions meshing with said sun gear, a vspider for :said pinions mounted -on isaid driven shaft, a :fixed ring-gear meshing with :said pinions, -ga `second runner formed on the first :stage .driver and forming :therewith La :second ,peripheral fluid chamber, overflow passages between said fluid chambers, a second driver :cooperating with ,said second runner, .gearing .between :said drive :shaft and said second .driver to :operate vsaid second driver at .a Ahigher .speed than .said rst driver, said overrunning clutch fprovidinggmeans whereby saidrst driver `may be @hydraulically driven bysaidfseconddriver :at a .higher speedvthan said rst driver is drivendirectly lfbyzsaid-drive shaft, and bleed means for reach fluid chamber.

9. In a ,hydraulic coupling. .a `.drive shaft, sa driven shaft, a .driver iforming.aperipheral fluid chamber aboutsaiddrive shaftgearineans including an overrunning clutch 'operativelyconnecting said driver to said zshatto turnfsaid driver :at any .predetermined desirablegear zratio, a runner inisaidifluid-.pchamber having .fasun gear .operatively :connected zthereto, planetary pinions meshing with said :sun igear, 'a :spider for i'said pinions mounted on :said .driven shaft, Va :xed ring-gear .meshing VK.with .said pinions, ya second runner iformed on :the ifirst :stage Vdriver :and forming therewith fa fsecond peripheral fluid chamber, cverflow passage's -fbetween `said ffluid chambers, ar-second {dri-ver cooperating with said second runner, gearing lb'etvveenl said `'drive shaft and `I'.saidse'cond driver to `foperate said second .driver :at fa lfhi'gher .fspeedilthan fsai'd frst .driver,

75 bleed-means iorachichamben said-overrunning clutch providing means whereby said first driver may be hydraulically driven by said second driver at a higher speed than said rst driver is driven directly by said drive shaft, friction clutch means between said first stage runner and said rst 5 stage driver normally released, and means responsive to iluid ow into said second chamber for operating said clutch means into engaged position for locking said rst stage runner and driver members together when said second stage 10 is brought into operation.

GEORGE W. BALL.

REFERENCES CITED The following references are of record in the 15 le of this patent:

UNITED STATES PATENTS Number Number Name Date Stock June 12, 1934 Fottinger Feb. 14, 1939 Speiser Sept. 29, 1942 Gunberg July 6, 1943 Jandasek Oct. 24, 1944 Pollard Feb. 6, 1945 Nallinger Oct. 2, 1945 Chilton May 2, 1946 Porter Feb. '11, 1947 FOREIGN PATENTS Country Date Great Britain Mar. 15, 1934 Italy Dec. 24, 1938 

